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The following topics were dealt with: power generation; equipment design; power system architecture; remote power feeding; decentralized power; grounding equipments; bonding equipments; VRLA; power storage; fuel cells; DC-DC converter control; inverter topology; UPS; photovoltaic energy; wind energy; power management; and power standards
Most of UPS-systems use batteries as back-up energy source. Usually here we find lead-acid batteries or NiCd batteries when its a high ambient temperature. If longer back-up times are required an additional diesel generator will provide the energy. This paper presents the results of some tests, where a fuel cell system generates the back-up energy on a 48 V level
All electrochemical energy storage systems can cause unsafe operating conditions when an uncontrolled current flow over an electrolyte path to ground occurs. The influences of different variables, intervening in such an event, have been explored with lead acid batteries of the VRLA/AGM type. The tests show that the ground short current ranges from 0.1 to ~50 mA and that direct line of sight through...
We have developed a VRLA battery (12 V- 65 Ah) for engine starters and a unit to detect deterioration. This battery can be used to start engine generators for telecommunications and ship engines. A capacity improvement of 14 to 67% has been achieved at a current discharge from 1 to 3 CA compared with the present battery by improving the positive grid and welding between cells. Consequently, we could...
We developed small cycle VRLA batteries that have a longevity of 3000 cycles, and confirmed that a UPS with these installed can supply stable power as an electrical energy storage system. This paper describes the batteries we developed and a UPS with an electric energy storage function
Lithium-ion batteries offer many attributes that are attractive for telecom reserve applications relative to flooded and VRLA technologies. These attributes include much higher energy density per unit weight and per unit volume, no hydrogen outgassing, no thermal runaway mechanism, and much lower steady-stage float current. Lithium-ion batteries are particularly attractive for sites where floor space...
Battery suppliers have answered the demands of their customers for less ventilation for equipment cabinets where batteries are included with solutions for central degassing on the VRLA-batteries. From several intelec's we have reports that the majority of hydrogen and oxygen produced by VRLA-batteries is lost through the case walls instead through the vents. Quantities are rarely reported and difficult...
Modeling and simulation of lead acid batteries is of utmost importance in predicting their operation for transportation systems such as hybrid and electric vehicles, for wheelchairs, for battery backup systems such as in UPS for computers and in telecommunication systems. Considerable effort is put into the selection of the appropriate battery model with specific regard to the battery state of charge...
Charge balance is known to be an essential consideration in series valve-regulated lead-acid (VRLA) battery applications. Conventional applications use passive equalization to maintain balance: periodic overcharge sequences. Active equalization uses external circuits to enforce charge balance without the need for overcharge. There is little published data to show the potential value of active equalization...
Based on 14 years experience with batteries in both MSC (mobile switching centre) and BTS (base transceiver stations), Vodafone D2 Germany is looking for alternatives to VRLA batteries especially in outdoor cabinets, to answer their changing requirements in terms of life and reliability, operational needs, impact on OpEx and CapEx, and environmental compatibility. The major challenges inside outdoor...
A new sensor will be presented, detecting concentration and temperature inside of lead acid batteries. Inserted into battery-management-systems like for example badicheq, the unit is able to indicate the state of charge under almost any circumstances. It is important to know the state of charge of a lead acid battery and it is easy to detect by measuring the acid level and the acid density. While...
Forty years ago, lead-acid batteries were already the dominating electrochemical storage system. As standby batteries, they mostly were used as large central batteries of flooded cells. Although they already represented a matured system, development went on, mainly in the areas of safety aspects and reduction of maintenance expenses. An important turning point was the introduction of the valve-regulated...
The use of lead-acid batteries as a back-up power source in telecommunication systems is well established. Valve-regulated lead-acid (VRLA) batteries have been the technology of choice and these 12 V products are connected in series to meet the higher voltage system requirements. Additional strings are used to increase capacity or allow redundancy, Atraverda has developed a component, based on a composite-laminate...
DeTelmmobilien (former Deutsche Bundespost) has established their own approval procedures for batteries. The regular testing of valve regulated lead acid batteries started in the year 1987. Tests, simulating the special need in the field of telecommunication power supply, have been invented. E.g. there are rectifiers in the field with and without boost charge characteristics. Therefore tests have...
The battery is a vital component in powering wireless networks, and for efficient and safe operation lead-acid batteries are typically kept at controlled operating temperatures (20degC to 25degC). This is a major requirement for base transceiver station (BTS) air conditioners. However, recent developments in electronics allow all active equipment in the BTS to operate reliably at much higher temperatures...
Active power has introduced a new energy storage technology that could replace lead-acid batteries in many applications. The new product, which stores energy in the form of heat and compressed air, will initially be packaged for use with uninterruptible power systems. However, with a few modifications, the technology can also be applied to remote telecommunications sites, for mobile telephone and...
Operating small industrial equipment such as measuring instruments, sensors or weather stations, at remote locations requires reliable off-grid power supplies. The most common solution are large batteries, even though there are some inconveniences for the operator. Especially in northern regions, batteries can freeze during winter and suffer non-reparable damage. The exchange is strenuous at remote...
The IEC 61427 Ed.2 applies to all lead-acid and nickel-cadmium cells and batteries for photovoltaic energy systems (PVES). This standard gives general information relating to the requirements of the secondary batteries used in PVES and to the typical methods of test used for the verification of batteries performances. The objective is to assist the specifier in the understanding of the purpose of...
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